"A civilization grows great when old men plant trees whose shade they know they shall never sit in." They do this so their sons and grandsons can enjoy this shade. No one plants trees for the sons and grandsons of strangers. Immigration is anti-civilization. https://twitter.com/mattklewis/status/1197602927776608263 …
"Trees" are both literal and metaphorical. The characteristics of trees - they're long-lived and slow growing and of immense benefit - apply to many facets of civilization both tangible and intangible: - a just legal system - a high trust culture - beautiful cities